Expert Comment: Confronting ‘mobesity’ is vital for the global electrification of transport

Published

24 Jun 2024

Expert Comment: Confronting ‘mobesity’ is vital for the global electrification of transport

The proliferation of large electric vehicles risks undermining the environmental and economic benefits of the green transport transition, argues Christian Brand, Professor of Transport, Energy and Climate Change at the Transport Studies Unit in the School of Geography and the Environment.

The transition towards electrified road transport is a cornerstone of global efforts to mitigate climate change. Whilst 14% of cars being sold are electric, there is an alarming shift towards the production and use of larger, heavier vehicles – ‘mobesity’ - which pose unique challenges to reducing emissions.

Dr Christian Brand, Professor in Transport, Energy & Environment

Whilst electric SUVs (e-SUVs) are three times more energy efficient their counterparts, they still require significantly more resources to build and have greater energy consumption, increasing their environmental footprint and undermining the potential gains from electrification. Even as the global fleet becomes electrified, the expected reductions in energy consumption and emissions may not materialize at the scale and pace required to reduce emissions in line with global climate targets.

The shift represents the most profitable models for manufacturers, sold at a premium for proportionally lower manufacturing costs. In 2022, e-SUVs constituted about 35% of all electric passenger car sales worldwide. Manufacturers have simultaneously released fewer new smaller models onto the market, which may be slowing the transition to smaller EVs. Together, this artificial scarcity—plus effective and targeted marketing—has shifted consumer preferences. Advertising is largely unregulated and has been shown to drive the demand for e-SUVs.

The increased demand for bigger batteries and more powerful motors in turn demand more lithium, cobalt, and other critical raw materials. The extraction and processing of these materials are energy-intensive and environmentally invasive, exacerbating the very problems that electrification aims to solve. The increased weight contributes to greater tyre and road wear, leading to more particulate emissions, which are harmful to both human health and the environment.

Clearly, the primary concern is the size of vehicles. To address the challenges posed by mobesity requires a nuanced approach that combines policy intervention, technological innovation, and shifts in consumer behaviour, such as:

Implement regulations and standards discouraging larger vehicles and promoting efficient, low-emission vehicles.
Introduce weight-, size-, or power-based taxation and CO2-emission graded taxes to incentivize smaller, energy-efficient EVs.
Stronger incentives for manufacturers to develop and market smaller EVs are essential.
Support advancements in battery technology to increase energy density and reduce material use, and support R&D in reducing toxic emissions from tyre wear.
Local governments should redesign urban spaces to discourage or ban large vehicle use and promote and invest in walking, cycling, and public transport.
Educate consumers on the environmental and economic impacts of large EVs (similar to smoking health warnings) and the benefits of smaller electric models.
International cooperation is needed to manage the global demand for critical minerals and promote a circular economy.

This commentary piece was originally published as a World View in Nature Energy.